Rainbow's founder Ritchie Blackmore is perhaps best known these days for two rather dubious achievements: he wrote the most pedestrian -- and most memorable -- guitar riff in history ("Smoke on the Water") and he pioneered the hairstyle that would later be employed by another guitar genius, Bernard Butler. But as metallurgists are well-aware, that's not an entirely balanced assessment of Blackmore's career.

Hailing from the grim little English resort of Weston-super-Mare, where I spent too many miserable family days-out to be objective about the place, Ritchie Blackmore cut his teeth as a guitarist in the '60s with a slew of bands: The 2 I's Coffee Bar Junior Skiffle Group, The Dominators, The Satellites, The Condors, The Outlaws, and Neil Christian and the Crusaders, among others.

Most notably, he did various stints with the Savages, the backing band for Britain's least successful politician and all-around monster raving loony, Screaming Lord Sutch, as did two other guitarists of some note, Jimmy Page and Jeff Beck. Blackmore even played in the 1966-67 version of Sutch's ensemble named Lord Caesar Sutch and the Roman Empire, who toured the UK and Germany playing gigs kitted out as Roman centurions.

In 1967 Blackmore hung up his centurion's outfit, accepted Jon Lord's offer to join the band that would soon become Roundabout (which would itself become Deep Purple), and went on to attain recognition as one of the most gifted and exciting British guitarists of the late '60s/early '70s. With Deep Purple -- alongside the likes of Black Sabbath and Led Zeppelin, of course -- he was instrumental in defining the sound of British heavy rock.

"Smoke on the Water" notwithstanding, Blackmore co-wrote some of Purple's most memorable numbers like "Speed King," "Child in Time," "Black Night," "Highway Star," "Strange Kind of Woman," "Burn," and "Mistreated," inscribing them all with a brand of virtuoso guitar work that imitators have been trying to reproduce ever since.

Following his departure from Deep Purple in 1975, Blackmore formed Rainbow (initially called Ritchie Blackmore's Rainbow), the subject of this installment of Universal's 20th Century Masters series. This release comprises representative material from each stage of the band's career and its constantly changing line-ups, from the 1975 eponymous debut album through 1983's nadir Bent Out of Shape.

Six of the eleven cuts here are drawn from the period of so-called "classic" Rainbow (1975-78), which saw Ronnie James Dio on vocals. These are undoubtedly the better tracks on the compilation. They best capture the sound of a band whose classically inflected guitar work, power chords, driving rhythms and melodic riffs would -- more directly than Blackmore's previous group perhaps -- inspire a subsequent generation of metal musicians the world over.

In addition to Ritchie Blackmore's guitar, a crucial ingredient of Rainbow's strongest material was Dio's commanding vocal performance and that dimension of the band's sound is well-documented on this release. Possessed of a voice that belied his famously diminutive -- even in heels -- stature, Dio had been vocalist with Elf, the band that Blackmore had commandeered to form Rainbow. Although Dio's lyrical preoccupations rarely strayed far from the ludicrous netherworld of dungeons and dragons, he delivered his tales of sword and sorcery with such power and sheer bombast that they were always totally compelling.

While the straight-ahead grind of "Man on the Silver Mountain" and the menacing charge of "Kill the King" encapsulate Rainbow's harder edge -- the latter showcasing the mighty drumming of the late Cozy Powell -- the outstanding tracks featured on this collection are Rainbow's slower, more textured numbers.

The building, hypnotic epic "Stargazer" from Rainbow Rising (1976), featuring the Munich Philharmonic Orchestra, is Rainbow's "Kashmir". Here the individual strengths of Rainbow's most potent line-up combine to sublime effect. Tony Carey's swirling keyboards, the solid, driving rhythms of Jimmy Bain on bass and Powell on drums, as well as the usual contributions of Blackmore and Dio, gel magically to yield not only the band's finest number, but a true metal classic.

No less monumental is the heavy blues epic "Mistreated." Although Blackmore wrote this number with David Coverdale for Deep Purple's 1974 album Burn, it became a live staple for Rainbow. This performance of the track from the 1977 album On Stage shows how fully Rainbow made the number their own -- particularly Dio, whose vocal interpretation gives Coverdale a run for his money.

Additionally, the lush, bluesy "Catch the Rainbow" from the band's 1975 debut and the melancholy, Renaissance-nuanced melodies of "Rainbow Eyes" from Long Live Rock 'n' Roll (1978) offer incontrovertible evidence of Rainbow's talents with regard to rock balladry.

By 1979, ex-Marbles vocalist Graham Bonnet had replaced Ronnie James Dio and Deep Purple cohort Roger Glover had been recruited to take over bass, as well as production duties, as Rainbow's sound began to move in a markedly different direction. I still recall the dismay I felt during my obligatory heavy rock phase in high school on listening to the first post-Dio album, Down to Earth. Blackmore appeared to be bent on turning one of the better hard rock acts of the '70s into a radio-friendly pop band. His efforts paid dividends almost immediately as the first single from the album, a cover of ex-Argent vocalist Russ Ballard's "Since You've Been Gone," gave Rainbow its first significant chart success in the UK. For 1981's Difficult to Cure, Bonnet was replaced by American vocalist Joe Lynn Turner and another Russ Ballard number, "I Surrender," reached number three in Britain.

Listening to "Since You've Been Gone" and "I Surrender" again in the context of this CD, it's impossible to deny that they were infectious songs and that they certainly deserved their chart places. By the same token, however, on Difficult to Cure in particular, it was clear that as Rainbow became more appealing to a broader pop audience, the band's music became less distinctive and imaginative. Worst of all, a cheesy keyboard sound was beginning to creep in alongside Turner's big, clean and entirely soulless vocals.

Years later, on moving to the US, I learned the term "hair band" and I became aware of the full horror that Rainbow may have been partially responsible for pioneering in the early '80s. That nascent folly declares itself more clearly on the other tracks from that decade that appear on this album -- the plodding "Stone Cold" and the awful "Power" from Straight Between the Eyes (1982), and the truly painful "Street of Dreams" from Bent Out of Shape (1983). These songs, especially the latter, have little to recommend them, sounding indistinguishable from much of the flaccid pomp rock that emerged in the mid-'80s to take the name of heavy metal in vain.